"Keep Designing!!!"

Parking meters can be a source of
inconvenience for police officers in that oftentimes, the LCD display is foggy
or difficult to read. Parking meters often have a default setting that display a
red background even when cars are not present. Our project, the Ultrasonic
Sensometer, seeks to address these issues by detecting when a car is present at
the parking meter and displaying an LED that visible from 10 meters away when
lit.

The Ultrasonic Sensometer implements an alert system that detects the
presence of a parked automobile within 2 meters. The parking meter sensor is
able to determine whether the car is legally parked, overdue, or soon to expire.
The Ultrasonic Sensometer receives two input signals from the parking meter: if
the parking meter has been paid and if five minutes or less are remaining on the
meter. In our demo, these signals are simulated by two external switches. The
device will signal the state of the parking meter, overdue or within five
minutes, with a light-emitting diode (LED). The project integrates a Parallax
PING))) sensor; an Arduino Uno with an ATmega328 processor; and circuit elements
including an LED, resistors, and switches.

To conserve energy, the device has a sleep mode which wakes itself up
approximately every fifteen minutes. The Ultrasonic Sensometer will run on the
parking meter's battery. Future directions involve making a wireless module to
alert the parker as well as the police as to the state of the parking
event.